import { createHash } from "node:crypto";
import { readFile } from "node:fs/promises";

import {
  evaluatePromotionReadiness,
  PROMOTION_FORMULA,
  type GateResult,
} from "../src/application/policies/promotion-readiness.ts";
import {
  loadCiGateContract,
  indexCiGateContract,
} from "./contracts/ci-gates.ts";
import { generateCiWorkflow, renderCiWorkflow } from "./generate-ci-workflow.ts";
import {
  ciContractReportSchema,
} from "./lib/ci-contract-report.ts";
import {
  validateInstallScriptPolicy,
  validatePackageScriptGraph,
} from "./lib/package-script-graph.ts";
import { writeValidatedJsonArtifact } from "./lib/validated-json-artifact.ts";

const removalFixtureMode = process.argv.includes("--reduced-removal-fixture");
const contract = await loadCiGateContract(process.cwd(), {
  mode: removalFixtureMode ? "removal-fixture" : "canonical",
});
const index = indexCiGateContract(contract);
const [packageDocument, nodeVersion] = await Promise.all([
  readFile("package.json", "utf8").then((value) => JSON.parse(value) as { scripts?: Record<string, string> }),
  readFile(".nvmrc", "utf8").then((value) => value.trim()),
]);
const packageScripts = packageDocument.scripts ?? {};
const failures: string[] = [];

if (!/^\d+\.\d+\.\d+$/u.test(nodeVersion)) {
  failures.push(".nvmrc must contain one exact Node.js semantic version");
}
for (const script of [
  "build:release-candidate",
  "verify:local-evidence",
  "verify:promotion",
  "generate:ci-workflow",
  "check:ci-workflow",
  "check:ci",
]) {
  if (!packageScripts[script]) failures.push(`package script missing ${script}`);
}
for (const removedScript of [
  "build:release",
  "verify:supply-chain",
  "verify:supply-chain:promotion",
]) {
  if (packageScripts[removedScript]) failures.push(`legacy package script remains ${removedScript}`);
}
if (/\b(?:build|rebuild)(?::[\w-]+)?\b/u.test(packageScripts["verify:promotion"] ?? "")) {
  failures.push("verify:promotion must not build or rebuild candidate bytes");
}
failures.push(...validatePackageScriptGraph(packageScripts, "check:ci"));
failures.push(
  ...validateInstallScriptPolicy(
    packageScripts,
    [...new Set(contract.commands.map(({ script }) => script))],
  ),
);

const immutable = index.gates.get("FE-GATE-015");
const immutableCommands = immutable?.commandIds.map((id) => index.commands.get(id)?.script);
if (JSON.stringify(immutableCommands) !== JSON.stringify(["build:release-candidate", "verify:local-evidence"])) {
  failures.push("FE-GATE-015 must build candidate bytes once and verify local evidence only");
}
const architecture = index.gates.get("FE-GATE-010");
if (!architecture?.commandIds.some((id) => index.commands.get(id)?.script === "check:ci")) {
  failures.push("a blocking gate must execute check:ci");
}
if (!architecture?.evidenceArtifactIds.some((id) => index.artifacts.get(id)?.path === "artifacts/quality/ci-contract.json")) {
  failures.push("FE-GATE-010 must publish the typed CI contract report");
}

const expectedGateIds = Array.from(
  { length: 26 },
  (_, index) => `FE-GATE-${String(index + 1).padStart(3, "0")}`,
);
const passingResults: Record<string, GateResult> = Object.fromEntries(
  expectedGateIds.map((gateId) => [gateId, "PASS"]),
);
const allPass = evaluatePromotionReadiness(passingResults);
const negativeFixtures: Array<{
  readiness: keyof typeof PROMOTION_FORMULA;
  failedGate: string;
  passed: boolean;
}> = [];
for (const readiness of Object.keys(PROMOTION_FORMULA) as Array<keyof typeof PROMOTION_FORMULA>) {
  const failedGate = PROMOTION_FORMULA[readiness][0];
  if (!failedGate) throw new TypeError(`${readiness} has no configured gates`);
  const evaluated = evaluatePromotionReadiness({ ...passingResults, [failedGate]: "FAIL" });
  const passed = evaluated[readiness] === false;
  negativeFixtures.push({ readiness, failedGate, passed });
  if (!passed) failures.push(`${readiness} did not fail closed`);
}
if (!Object.values(allPass).every(Boolean)) failures.push("all-PASS formula did not produce every readiness state");

const renderedWorkflow = renderCiWorkflow(contract);
const workflowCheck = await generateCiWorkflow({
  root: process.cwd(),
  contract,
  check: true,
});
if (!workflowCheck.matches) {
  failures.push(
    `generated workflow drift at byte ${workflowCheck.firstDifferenceByte ?? "missing"}, line ${workflowCheck.firstDifferenceLine ?? "missing"}`,
  );
}
let checkedWorkflowBytes = Buffer.from(renderedWorkflow, "utf8");
try {
  checkedWorkflowBytes = await readFile(workflowCheck.target);
} catch (error) {
  failures.push(`generated workflow is unreadable: ${error instanceof Error ? error.message : String(error)}`);
}
const report = ciContractReportSchema.parse({
  schemaVersion: 2,
  nodeVersion,
  gateCount: contract.gates.length,
  commandDefinitionCount: contract.commands.length,
  commandReferenceCount: contract.gates.reduce((total, gate) => total + gate.commandIds.length, 0),
  artifactCount: contract.artifacts.length,
  jobCount: contract.jobs.length,
  workflowSha256: createHash("sha256").update(checkedWorkflowBytes).digest("hex"),
  durationStatus: contract.retention.durationStatus,
  negativeFixtures,
  failures,
  passed: failures.length === 0,
});
await writeValidatedJsonArtifact({
  path: "artifacts/quality/ci-contract.json",
  schema: ciContractReportSchema,
  value: report,
});
if (failures.length > 0) {
  process.stderr.write(`CI contract failed:\n${failures.join("\n")}\n`);
  process.exit(1);
}
process.stdout.write("CI contract: 26 gates, strict v2 graph and generated workflow model PASS\n");